Disclosed is an encapsulation barrier stack, capable of encapsulating a moisture and/or oxygen sensitive article and comprising a multilayer film, wherein the multilayer film comprises : one or more barrier layer(s) having low moisture and/or oxygen permeability, and one or more sealing layer(s) arranged to be in contact with a surface of the at least one barrier layer, thereby covering defects present in the barrier layer, wherein the one or more sealing layer(s) comprise(s) a plurality of dendrimer encapsulated nanoparticles, the nanoparticles being reactive in that they are capable of interacting with moisture and/or oxygen to retard the permeation of moisture and/or oxygen through the defects present in the barrier layer.